Project Summary/Abstract 1 Quality of care has become a significant component of provider evaluation and reimbursement. As alternative payment 2 models gain popularity and the new Merit-Based Incentive Payment (MIPS) program rolls out, how quality is defined and 3 measured will become increasingly important for patients, providers and payers. In the field of cardiology, most quality 4 metrics are based on findings from large, randomized trials. While robust, randomized trials can be limited in their 5 generalizability, owing to narrowly defined enrollment criteria and the underrepresentation of certain patient populations. 6 This can result in a mismatch between the population in which a therapy has been proven effective and the population in 7 which quality metrics require it use. This, in turn, can create a system of quality measurement that inadvertently incentives 8 non-evidenced based practice or unfairly penalizing certain providers. An example is the use of neurohormonal therapy in 9 elderly patients with heart failure and reduced ejection fraction (HFrEF). Neurohormonal therapies, which include 10 angiotensin converting enzyme inhibitors (ACEi)/angiotensin II receptor blockers (ARB) and beta-blockers, are the 11 cornerstone of HFrEF therapy and their use now defines quality in HFrEF care. While neurohormonal therapies are 12 undoubtedly beneficial in the vast majority of HFrEF patients, elderly patients ?75 years old were underrepresented in the 13 landmark studies that evaluated the efficacy and safety of these drugs. Since neurohormonal therapies carry a non-trivial 14 risk of side effects, it is possible that the short term risks of therapy outweigh the longer term benefits in certain elderly 15 patients. At present however, neither clinical guidelines nor quality metrics account for this known heterogeneity among 16 elderly HFrEF beneficiaries. To better understand the impact of neurohormonal therapy on elderly HFrEF patients, 17 determine how best to use neurohormonal therapy in elderly HFrEF patients and more effectively measure quality of care 18 among elderly HFrEF patients, a 3-part analysis using administrative, registry and qualitative data is proposed. The 19 project aims to (1) use Medicare data to determine whether and how the clinical benefits of neurohormonal therapy vary 20 by age; (2) to use the national registry data linked with Medicare data to determine characteristics that predict likelihood 21 to benefit from neurohormonal therapy among elderly HFrEF patients and simulate the effectiveness of a targeted 22 approach to therapy using the identified characteristics; and (3) to use semi-structured patient interviews to determine the 23 aspects of care that define ?high quality care? for elderly HFrEF patients. This work has the potential to both improve the 24 quantity of care and the quality of life for elderly HFrEF patients as well as improve our current method of quality 25 measurement in heart failure. First, an assessment of existing variation in outcomes with neurohormonal therapy, by age, 26 will define the scope of the issue and the potential for improvement. Secondly, identification of the patient-level 27 characteristics associated with a high likelihood of benefit (or harm) from neurohormonal therapy among elderly HFrEF 28 patients will enable improved clinical care and the refinement of current quality metrics. Finally, a qualitative assessment 29 of elderly HFrEF patient priorities will lay the foundation for future research to develop the next generation of quality 30 metrics that incorporate patient preferences.